FREE TN LLE Services, Feeders, Branch Circuits Questions and Answers

Question 1

An overhead service drop, with a voltage not exceeding 300V between conductors, passes over a residential roof with a 3-in-12 pitch.
According to NEC 230.24(A), what is the minimum vertical clearance that must be maintained above the roof surface?

Accepted Answer

8 feet

Answer

18 inches

Answer

3 feet

Answer

10 feet

Question 2

An electrician is installing a 120/240V multiwire branch circuit to supply two separate kitchen countertop receptacle circuits. Which of the following is an NEC requirement for this type of circuit?

Accepted Answer

A means must be provided to simultaneously disconnect all ungrounded conductors.

Answer

The neutral conductor must be one size larger than the ungrounded conductors.

Answer

The circuit must be protected by two single-pole breakers on the same phase.

Answer

The circuit is not permitted to supply kitchen countertop receptacles.

Question 3

What is the minimum feeder conductor ampacity required for a load consisting of a 40-amp continuous load and a 30-amp noncontinuous load?

Accepted Answer

80 amps

Answer

70 amps

Answer

87.5 amps

Answer

100 amps

Question 4

According to NEC 230.70(A)(1), where must the service disconnecting means for a one-family dwelling be located?

Accepted Answer

At a readily accessible location either outside or inside nearest the point of conductor entrance.

Answer

In the center of the building for shortest branch circuit runs.

Answer

Only inside the attached garage.

Answer

In a locked cabinet in the basement.

Question 5

When calculating the load for a branch circuit supplying a fixed multioutlet assembly (e.g., plugmold) in a commercial building where appliances are not likely to be used simultaneously, what is the standard load allowance per section?

Accepted Answer

180 VA for every 5-foot section or fraction thereof

Answer

180 VA for every 1-foot section

Answer

1500 VA for the entire assembly

Answer

600 VA for the first 10 feet and 180 VA for each additional 5 feet

Question 6

A main-lug-only (MLO) panelboard is installed as a subpanel in a workshop. According to NEC 408.36, which of the following is required?

Accepted Answer

It must be protected by an overcurrent device on its supply side.

Answer

It must have a maximum of six circuit breakers.

Answer

It must be located within sight of the service disconnect.

Answer

It can only be used in residential occupancies.

An overhead service drop, with a voltage not exceeding 300V between conductors, passes over a residential roof with a 3-in-12 pitch.According to NEC 230.24(A), what is the minimum vertical clearance that must be maintained above the roof surface?

An overhead service drop, with a voltage not exceeding 300V between conductors, passes over a residential roof with a 3-in-12 pitch.
According to NEC 230.24(A), what is the minimum vertical clearance that must be maintained above the roof surface?